Multiverse

Krona was a member of the ancient race of powerful immortals from the planet Maltus, who later immigrated to Oa and called themselves the Guardians of the Universe. He was a scientist obsessed with observing the creation of the universe, despite an Oan legend that said discovering that secret would cause a great calamity. Krona created a machine that allowed him to see into the moment of creation. Somehow, his experiment disrupted the process of creation, with terrible consequences, and caused the creation of not a single universe, but the generation of an infinite number of universes. Life, customs, and languages evolved on each universe's Earth almost exactly at the same rate.

The Multiverse consisted of multiple versions of the universe existing in the same physical space, but separated from each other by their vibration resonances. Some universes are behind or ahead of present time on another universe based on its vibration resonance which creates a time flux. Once a year, the temporal matrices of the universes are at their closest point, and people can travel to another universe by using a dimensional transporter. Two versions of the same person can exist in one universe and occupy the same space and time because they vibrate at different speeds.